Carburetor



June-6, 1933- J. W. ALLBRIGHT 1,913,321 v T CARBURETOR- Filed April 9 1932 I Inventor Attorneys 50 efficiency.

Patented June 6, 1933 1 JOHN w. Annamaria or Application filedApril 91,51 932; ser1a1 1 N6l co r,23o. 1

My invention relates to carburetors for internal combustion engines andhas particui lar reference to a carburetorw in which the quantity of fuel and quantity of air supplied 5 to the engine are maintained insubstantlally 1 constant relative proportion independent of a, the speed of operationof; the engine; In theart of supplying mixed fuel and ;a1r to an internal combustion engine, many at tempts have been made to maintain a con- 1,

stant relation between, the amountiofair and I theamount of fuelfisupplied to the engine under varying 1 conditions of operat on, as, for example, by automatically increasing the l 115 fuel injection openingin accordance with the air through the cary -ifollowingiyspecifications,' read in connection degree of suction of buretor.- 1 A A A 1 Howevenall of these methods have been unsuccessful, due to theinability to devise 0 an accurately graduatedsupply lof fuelfr'om theinjection jetupon small variations 111' the suction through the carburetor. 1 a 1 It is, therefore, an object of my; invention 1 to provide acarburetor in which a fuel' control valve is automatically actuated in, re-

Another object of my invention isfto pro- 3 vide a device of the characterset forth, in:

1 which the injection'of fuelinto theaijr stream 0 of the carburetor occurs in aVenturi'tubeso that the velocity of; air passin'gthroughthe tube causes an intimate mixing of air and Nfuelp 1 1 A 1 ,1 Another object of my invention is to pro- 5 vide a carburetor as set forth in the preceding paragraph in which the Venturi tube, 1 is adjustable relative to the, opening of the injection jet to permit the setting of the ven- 1 j turi relative to the jet to achieve maximum graduation of the a of the-,T is; directed substantially at aright of the invention is to provide a carburetor? in-which a valve for, controlling theamount, of fuel supplied through the injection jet comprises a cylindrical valve having-a plurality} of progressivelyenlarged grooves, a'therearound, permitting accurate amount ofvfuel supplied, to thejetwqy 1,11 1 1 1 .Anotherobject,of the invention is to pro-- videiaicarburetor of the character set forth in WlllClI= fuel may be supplied to the injection 1 jetfrom a float chamber or may be supplied direct from afuel; tank without the employment of a float chamber. 1 i 1 Other objects and advantages of the inven tioIi mute apparent from a study of the with the accompanyingdrawing, wherein Figure 1 is a1vertical sectional view, taken through acarburetor constructed in accord 7 ance with my invention; 1 3 Figure 2 is an end elevational view, shown partly in1 section,-of the carburetor illustrated in Figure1; A 1 1 Figure 3lisa detail View of the construction of a fuel supply valve, which may be employed inthe practice of my invention; an 11 A 1 j 1 1 Figura is i an end elevational view of a modified form of carburetor which may be employed in the practice of my invention. Referring to the drawing, 1 have illustrated in Figure a carburetor having a body aneihberl, illustrated as being substantially cubical in configuration to form a housing chamber-' 2 in Whichan injection jet 13* may bemounted, The injection jet 3 is preferably "formed 1 of a T-shaped tubular member-s4 threadedly secured at one end 5 thereof: into a plate 6v constituting one side of the body member 1 If desired, the plate I) may be formed separately from Y the body 1 memberl and attached thereto as by means of screws. 7,,the plate being provided with an inwardly extending shoulder 8 engaging thejperiphlery of a circular recess 9 formed in the material of the body member 1. 1; By; referring particularly to Figure2, it

will {b6 observed that the cross member 10 mo jection jet outlet 14. The outlet 14s is illustrated as being formedof substantiallytubular shape, having afu'el p'assage15there-' through extending into communicationwith the interior of the tubular member 4 and having its outer end terminating: inza flared opening 16. Preferably, the fuel passage 15 is of such size-as to=accommodate the maximum quantity of fuel which w i llberequire'd for the engine 1 under maximum conditions of speed and load.

The j et outlet. 14 is illustrated .as :eX-tending along the axis of a tubulanmixture-outilet 17 which may be'connected by meanss-of a flange 18 to the usual inlet manifold-of the internal combustion: :enginenwith "-Whl'(3hmy carburetor. may be associated. iThe outlet 17 may be provided 'with ithe aisual :butterfly thr ottle valve ;19 employed rfor controlling the amount of :-mixture :zaldmitted lto'it-he engine. 1

It Will .also; bee-observed: that thexmixture outlet'1'7 is provided-With. an inner. tube. 20

J :fitted within the passageithreughr the) :mix-

ture. outlet 17, the inner i walls: of theiinner tube 920-? being of: such-configuration ..as to constitute; axVenturi tube through whichxair and fuel must be drawnzinto the engine. :It

'WVdll be observed: that. the: outer :wa'llseof. the

tube 20 conform 'with gtheinnei" walls :of. the outlet 17 so that the tube; 20 may-ibeiadjusted to any; position along the :lengthlofthe outlet :17. Thus the nearest portion o'f thewenturi may be: located; immediately; abovethe fuel in ection outlet, or may be adjusted .some

,1 distance above-the Esame, onunayi beiadjusted 1 below the same toprovide theconstrietion of the passage therethrough at' the most desir- :,able point to insure maximum suctioniof' fuel through the passage 15 sandito insureathe maximum: mixing eifectrpbetweeni. theeair and fuel.

An air-entrance inlet 21ais illustrated cominunicatingewith the interionrchambenof the body member-1, the air entrance inletbeing prefer-ably formed upon: a nipple 22 threaded into one sideof" the: body member ..1,-:as. is

"indicated atir23. Mounted :supon zthe outer end of the nipple. 222 Idiave illustratedia choke assembly including :a tubular entrance Inorder to properly coordinate the amount of fuel-which is supplied to theengine in ac -cordance with the amountef air supplied to the engine, a fuel control valve 27 may be employed, mounted in and slidable along the body member 4 of the injection jet assembly. The valve 27 is illustrated as being provided with a plurality of annular grooves 28, the grooves toward the right hand end of the 'valve'27 being relatively large, while the size of thegrooves progressively diminish as they approach the left hand end of the valve 27. .Eachofthese grooves may be selected of suchdimensions as will permit the flow there- ..around of a predetermined quantity of fuel under conditions of substantially constant Epressure.

From an inspection of Figure 1, it will be -'-bbserve'd'that the fuel entrance ll to the jet *4 lies in the same vertical plane 'as the fuel fpassagelfiof the injection outlet 14, so that at the instant. that any one of the 1 grooves i'28-isaligned with the fuel entrance, the-same -groove-is aligned with the'fuel passage 15 so that the amount of 'fuel which may pass "around that particulargroove is the amount "ef fuel-supplied to the fuel passage 15.

"By referring'to -Figu gl it will be ,9190

"served-"that"the fuel valve 27 is normally pressed toward the right, as shown in this figure; by means of a compression spring'29,

seated-i-n-a suitable recess formed in the 7 end of the valve" 27 ,fthe-other nd f th -=seat-' 34f to substantially close the air inlet to the carburetor. *If desired, suitable small openings :35 may be formed in the cap 33 to permit the ingress of asufiicient amount of air to supply an-idlingmiXtur-e to the engine, even though the cap-33 is :seated: upon the -seat'34.

-With the construction I herein described, it will be observed: that normally the valve this spring, the cap-' 33 will seat-upon the 1110 27is in such-positionas to provide the minimum quantity of fuel to be injected into the carburetorywhile the openings 35 in the cap 33 permit the ingress of just the correct amount of-air for such minimum amount of f'uel to maintain the-idling speed of the mo- Z tor to' which the carburetor is attached.

However, as the throttle valve 19 is opened forthe purpose of speeding upthe' engine, 1 the inc-reasedsu'ction will cause the cap 33 to j be drawn inwardly (that is, to tllGlBftffiS through the carburetor.

viewed in Figure 1) by the suction created in the mixing chamber, and when so drawn the valve2? will automatically assume a position corresponding to the degree of suction This operation will cause another ofthe grooves 28 to be aligned with the fuel passage 15, corresponding to the amount of suction in the carburetor. By

I properly adjusting the spring 29 to the suction of the particular engine to ,which my carburetor is attached, the particular groove aligned with the fuel passageat any given ,value of suction may be of just the correct or tapered valve construction in whlch relatively small amounts of longitudlnal movement of the valve member causes a relatively great change in the orifice between the valve and the seatpreventing minute and accurate graduations of the fuel opening.

It will be observed that the valve seat 34 may be adjusted manually along the line of movement of the valve 27 to thereby permit adjustment of the seating of the fuel valve 27 to correspond to the degree of suction created by any particular engine. This permits the adjustment of the idling speeds and also permits adjustment of the quantity of fuel supplied to the engine in accordance with the character of the engine to which the device is attached. p

In the embodiment of my invention shown herein, the carburetor is adapted to what is known as the updraft type of mixture inlet; that is, the carburetor is illustrated as having the stream of air drawn into the carburetor and then drawn upwardly into the engine. By employing a body member of the character set forth herein, my carburetor 1s equally adapted to a down draft system, without altering the point of fuel entrance into the carburetor. This is accomplished by providing the upper and lower walls of the body member with relatively large openings 36 and 37 therethrough, these openings preferably being of the same dimensions and preferably being circular, so that the IIllX- ture outlet tube 17 may be removed from the top of the carburetor housing and be placed upon the bottom thereof, while the bottom closure plate 38 may be removed from the bottom and placed upon the top of the car buretor housing to close the opening 36.

In like manner the mixture outlet tube 1'? may be placed upon the side of the carburetor in the opening 39 therein, if it is desired that the outlet shall lead from the side desired to float-feed of the carburetor instead of fromthetop or 3 bottom.

. It will also be observed that the jet tube member 4 has a downwardly extending boss 40 in alignment with the boss 13 so that the, fuel outlet 14 may be inserted in the opening 40 instead ofthe opening 16 in the event the carburetor is used for down draft. Asuitable screw plug 41 may be employed to close the opening through thebosses 40 or 13, spectively, which is not in use. p

By referring particularly to Figure 2, it will be observed that the employment of the Venturi tube 20 will permit the suction of the incomingair to suck fuel through theL-i fuel passage 15 and this suction may be so great as to draw fuel direct from the suitable fuel tank, it being preferable to provide a suitable reservoir 42 near thecarburetor to maintain therein some fuel to permit easy startmg. Thls reservoir may be comprised of a coil of the fuel supply tube,if desired,

and is preferably provided with a check valve 43 preventing back draining of thefuel from the reservoir when the engine is stoppedgc thereby. retaining fuel in the reservoir for starting purposes.

Also, if desired, my carburetor may be employed with the ordinary float chamber reservolr, as shown in Figure 4, the reservoir:

being indicated by the reference character 44 formed upona suitable plate 45 which may be substituted for the plate 46 shown in Fig ure 2, so that the reservoir 42 maybe removed from the carburetor and the floatil chamber 44 inserted in place thereof if'it is the system'for the carburetor.

While I have shown and described the preferred embodiment of my invention, it

to be understood that .I do not wish to be limited to the details of construction shown herein, except as defined in the appended claims.

I claim: i

1. In a carburetor, means defining an air passage through said carburetor, a fuel injector in said passa for admitting fuel to stream of air passing through said car.

buretorrsaid injector having a fuel inlet and a fuel outlet spaced from each other. a valve for variably controlling the quantity of fuel injected into said air stream, having valve stem formed. witha plurality of grooves, each of which is selectively alignable with hoth 120 the fuel inlet and the fuel outlet and each of which is formed witl'i a different area.

2. In a carburetor, means defining an air passage through said carburetor, afuel in jector in said passage for admitting fuel to reita stream of air'passing through said carbu retor, said injector having a fuel inlet and a fuel outlet spaced from each other, a valve for variable controlling the quantity of fuel injected into said air stream, having a valve system formed with a plurality" of 'gr0oves,;- each of Which is selectively alignablewith both the fuel inlet and the fuel outlet-and sure of air passing through said passage for each of which is formed With a difierent area, and means operably responsive to the pres movlng said valve stem to bring any one of said grooves into alignment with said fuel inlet and fuel outlet corresponding to the pressure of the air.

3. In a carburetor, means defining an air passage through said carburetor, a fuellin- ,jector in said passage for admitting fuel to a. stream of air passing through said carburetor, said injector having a fuel inlet and a fuel outlet spaced from each other, a valve for-variably controlling the quantity of fuel injected into said air stream having. a valve stein formed With a plurality of spaced grooves thereon, each of Which is formed -With a different area diminishing as said groove 18 spaced further from one end of said ,an-air passage throu h said carburetor-, a

fuel injector in said body member for adanitting fuel to a stream of air passing therethrough, said injector havlnga fuel. inlet and afuel outlet spaced-from each other and having-a valve for variably controlling the quantity of fuel injected into said air stream including a valve stem having a plurality of spacedcircumferential grooves therearound each allgnable with said fuel inlet andsaid 1 fuel outlet to provide a passage therebetween,

each of said grooves being of a different area, an-air inlet in said body member, means on said valve stem adjacent said air inletfor closing said air inlet and operable in response to pressure of air entering said body member for moving said Valve stem relative to said fuel inlet and outlet to align any one of the grooves thereon with said fuel inlet and out let, depending upon the pressure of air passing through said air inlet.

' 5. In a carburetor, a body member forming anair passage through said carburetor, a fuel injector in said body member for-admitting 7 fuel to a, stream of air passing tierethrough,

said injector having a fuel inlet and a fuel outlet spaced from each other and having a :valve for variably controlling the quantity of fuel injected into said air stream including a valve-stemhaving a. plurality of spaced circumferential grooves therearound each alignable with said fuel inlet and said fuel outlet to'provide a passage therebetween,

each of saidgrooves beingof a difierent area,

van air inlet in said body me1nber,an air valve on said valve stem,a seat-for, said valve located in said an inlet whereby pressure of air entering said inlet Wlll move said air valve from said seat to align any one of the grooves on saidvalve stem with said fuel inlet and fuel outlet dependingupon the pressure of said air, and meansfor-adjusting said air valve seat toward and away from said injectorto normally align any one of said grooveswith said fuel inlet and outlet to thereby adjust the quantity of fuel supplied to-said carburetor for idling operation.

Signed at Los Angeles,California, this 2nd day of April, 1932.

JOHN 'W. 'ALLBRIGHT. 

